Abstract
A wall hook for fixing in an anchoring substrate. In order that a hook part of the wall hook can be aligned at any desired spacing from the anchoring substrate, the wall hook includes a stop element which extends away from a hook element parallel to a longitudinal axis, the hook part being rotatable relative to the stop element about the longitudinal axis.
Claims
1. A wall hook for fixing in an anchoring substrate, having a fixing element and a hook element, wherein the fixing element has a shank which is elongated in the direction of a longitudinal axis of the wall hook, and wherein the hook element has a shank receiver for receiving the fixing element, and a hook part which projects outwards from the shank receiver to one side radially with respect to the longitudinal axis, wherein the wall hook comprises a stop element which extends away from the hook element parallel to the longitudinal axis and has an extent radially with respect to the longitudinal axis that is smaller than that of the hook part; and the hook part is rotatable relative to the stop element about the longitudinal axis; or the stop element is separably connected to the hook element by means of a predetermined breaking point in such a way that the predetermined breaking point is severable by rotation about the longitudinal axis.
2. The wall hook according to claim 1, wherein the stop element tapers wedge-like or sleeve-like at its end that faces away from the hook part.
3. The wall hook according to claim 1, wherein the length of the stop element in the direction of the longitudinal axis is greater than its extent radially with respect to the longitudinal axis.
4. The wall hook according to claim 1, wherein the stop element has grooves and/or ribs running in the direction of the longitudinal axis for preventing rotation.
5. The wall hook according to claim 1, wherein the stop element is connected to the hook element by means of a frictional and/or interlocking connection.
6. The wall hook according to claim 1, wherein the stop element and the hook element are made from the same material.
7. The wall hook according to claim 1, wherein the stop element and the hook element consist of different materials.
8. The wall hook according to claim 1, wherein the stop element consists of a plurality of parts.
9. A fixing arrangement having a wall hook according to claim 1 and an anchoring substrate in which the wall hook is fixed, wherein the stop element has been at least partly introduced into the anchoring substrate; and the hook part is rotatable relative to the stop element about the longitudinal axis.
10. A method for fixing the wall hook according to claim 1 in an anchoring substrate, having the following steps: a) introduction of the fixing element into the anchoring substrate in such a way that the stop element enters into engagement with the anchoring substrate, and b) rotation and alignment of the hook part relative to the stop element once the stop element has been at least partly introduced into the anchoring substrate.
11. The method according to claim 10, including step: c) severing of a predetermined breaking point, which is arranged on the wall hook between the stop element and the hook element, during or after the introduction of the fixing element and the stop element into the anchoring substrate.
12. The method according to claim 11, wherein the fixing element is a screw; and the severing of the predetermined breaking point takes place as the screw is screwed into the anchoring substrate.
13. The wall hook according to claim 6, wherein the stop element and the hook element are made from the same plastics material.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The invention is explained in greater detail below with reference to three exemplary embodiments shown in the drawing, wherein
[0025] FIG. 1 shows a first wall hook according to the invention in a side view;
[0026] FIG. 2 shows the first wall hook according to the invention in a sectional view;
[0027] FIG. 3 shows the hook element of the first wall hook according to the invention in a perspective sectional view;
[0028] FIGS. 4 to 9 show the fixing of the first wall hook according to the invention in an anchoring substrate;
[0029] FIG. 10 shows a second wall hook according to the invention in a perspective sectional view; and
[0030] FIG. 11 shows the hook element of the first wall hook according to the invention in a sectional view.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIGS. 1 to 9 show a first wall hook 1 according to the invention. The wall hook 1 consists of a screw 2 made of steel as fixing element 3, a hook element 4 and a stop element 5, which is arranged in front of the hook element 4 in the introduction direction E. The introduction direction E is the direction in which the screw 2 is screwed into an anchoring substrate 6 (see FIGS. 4 to 9). A shank 7 of the screw 2 extends along a longitudinal axis L of the wall hook 2 and has a screw tip 8 at its front end in the introduction direction E and at its rear end a screw head 9 having a tool receiver for a rotary tool (not shown). A thread 10 extends from the screw tip 8 over a large portion of the shank 7 towards the screw head 9. The shank 7 of the screw 2 is installed in a sleeve-like shank receiver 11 of the hook element 4, which shank receiver entirely encompasses the shank 7 in the circumferential direction. The shank receiver 11 passes fully through the hook element 4 in the direction of the longitudinal axis L and has in a rear region a conical widened portion 18 for receiving the screw head 9. Formed in one piece with the shank receiver 11 there is arranged a parallelepipedal cantilever arm as hook part 12 which projects outwards from the shank receiver 11 to one side radially with respect to the longitudinal axis L. In front of the hook element 4 in the introduction direction E there is arranged the stop element 5 which extends away from the hook element 4 parallel to the longitudinal axis L. The extent of the stop element 5 in the direction of the longitudinal axis L is approximately three times as great as its extent radially with respect to the longitudinal axis L which corresponds to the radius of a circle circumscribing the stop element 5, which circle lies in a radial plane with respect to the longitudinal axis and the centre point of which lies on the longitudinal axis. In contrast, the radial extent of the hook part 12 is more than three times as great as that of the stop element 5, so that, for example, an eyelet of a picture (not shown) can be supported on the stop element 5 and, by means of the hook part 12, is secured against slipping off the wall hook 1 in a direction opposite to the introduction direction E.
[0032] The stop element 5 is a hollow-cylindrical sleeve which has a cylindrical opening 13 for the shank 7 of the screw 2. The stop element 5 tapers conically at its front end in the introduction direction E that faces away from the hook part 12 or tapers wedge-like in the region of the ribs 14. The ribs 14 are arranged on the surface of the stop element 5 and run in the direction of the longitudinal axis L, as do grooves 15 arranged between the ribs 14 in the circumferential direction. At its rear end in the introduction direction E, the stop element 5 has a trapezoidal circumferential tongue 16, the radial extent of which with respect to the longitudinal axis L increases in a direction opposite to the introduction direction E and engages behind a complementary counter-tongue 17 of the hook element 4, so that the stop element 5 and the hook element 4 are interlockingly connected to one another so as to be axially fixed. The stop element 5 and the hook element 4 are, however, rotatably connected by the interlocking connection, that is to say the hook part 12 is rotatable relative to the stop element 5 about the longitudinal axis L. The hook element 4 and the stop element 5 consist of different materials. The hook element 4 is made in one piece from a glass-fibre-reinforced polyamide, while the stop element 5 consists of a polyoxymethylene (POM). The stop element 5 is produced together with the hook element 4 in a two-component injection-moulding process, wherein first the stop element 5 is injection-moulded and then the stop element 5 is overmoulded in the region of its tongue 16 with the material of the hook element 4, the counter-tongue 17 being formed around the tongue 16.
[0033] For fixing the wall hook 1 in an anchoring substrate 6, which is a wooden beam in the exemplary embodiment, the screw 2 is first screwed into the anchoring substrate 6, as shown in FIGS. 4 and 5. The anchoring substrate 6 is part of a wall and in this case the hook part 12 is first aligned perpendicularly upwards, as shown in FIG. 4. In that position the hook part 12 is initially held in the desired alignment by a user while the screw 2 is being screwed into the anchoring substrate 6. During further screwing-in, the stop element 5 is introduced with the screw 2 into the anchoring substrate 6 so that it enters into engagement with the anchoring substrate 6. As a result of the spike-like or nail-like taper of the front end of the stop element 5, the stop element 5 is easily able to penetrate into the wooden beam as anchoring substrate 6, during which the grooves 15 together with the ribs 14 act as anti-rotation elements which prevent the stop element 5 from twisting about the longitudinal axis L (FIGS. 6 and 7). The stop element 5 is then fixed against rotation relative to the anchoring substrate 6. The screw 2 is screwed into the anchoring substrate 6 until the desired spacing between the hook part 12 and the anchoring substrate 6 has been achieved (FIG. 7). As a result of the further penetration of the stop element 5 into the anchoring substrate 6, the resistance to penetration into the anchoring substrate 6 is increased on account of the increasingly large cross-section of the stop element 5, so that the screw head 9 is pressed more strongly against the conical widened portion 18. As a result, as the screw 2 is screwed in, it is possible for the hook element 4 to be unintentionally twisted about the longitudinal axis L (FIG. 6) and be no longer aligned upwards as desired. Since the hook element 4 and the stop element 5 are rotatable relative to one another, the hook element 4 can then be rotated about the longitudinal axis L relative to the stop element 5, which is connected to the anchoring substrate 6 so as to be fixed against rotation, and aligned in the desired position, as shown in FIGS. 8 and 9. The hook part 12 of the wall hook 1 then has the desired alignment and the desired spacing. Spacing and alignment are adjustable independently of one another. The stop element 5 acts as stop and counter-bearing for the hook element 4, which is pressed against the stop element 5 with the screw 2, so that a frictional force acts between the hook element 4 and the stop element 5, which frictional force, once the hook part 12 has been aligned, prevents the alignment of the hook part 12 from being altered by jolting or contact, as may act on the hook part 12, for example, during mounting of an eyelet of a picture to be hung.
[0034] The further exemplary embodiments shown in FIGS. 10 and 11 have many aspects in common with the first exemplary embodiment. Components having the same function are therefore denoted by the same reference symbols and the following description is limited to the differences with respect to the first exemplary embodiment.
[0035] The wall hook 1 according to the invention shown as second exemplary embodiment in FIG. 10 differs from the wall hook 1 of the first exemplary embodiment of FIGS. 1 to 9 in essentially two features: firstly, the stop element 5 consists of a plurality of parts. A spacer element 19 belonging to the stop element 5 is arranged in front of the hook element 4 in the introduction direction E and behind a front part 20 of the stop element 5, which front part has the taper and the ribs 14 and grooves 15 for preventing rotation. As a result of the introduction of the spacer element 19 between the front part 20 and the hook element 4, the hook part 12 can be arranged at a greater distance from the anchoring substrate 6. Secondly, the front portion 20, the spacer element 19 and the hook element 4 are connected by frictional engagement but not by interlocking. In this exemplary embodiment, complementary hollow-cylindrical portions 21 engage frictionally in complementary hollow-cylindrical recesses 22 in such a way that they connect the three parts 4, 19, 20 to one another by frictional engagement so as to be axially fixed and rotatable.
[0036] In contrast, the hook element 4 is made in one piece with the stop element 5 of the wall hook 1 of the third exemplary embodiment shown in FIG. 11 from a plastics material, so that the stop element 5 and the hook element 4 consist of the same material, that is to say of glass-fibre-reinforced polyamide. The hook element 4 and the stop element 5 are connected to one another by means of a predetermined breaking point 23 which is in the form of a portion of greatly reduced wall thickness between the hook element 4 and the stop element 5. The injection-moulded skin forming the predetermined breaking point 23 connects the two elements 4, 5 so as to be axially fixed and captive. If during fixing, however, the hook element 4 is twisted relative to the stop element 5, which is connected to the anchoring substrate 6 so as to be fixed against rotation, the predetermined breaking point 23 will be severed so that the hook element 4 can be rotated relative to the stop element 5 about the longitudinal axis L for the purpose of alignment. The severing can occur as early as during the screwing-in of the screw 2 into the anchoring substrate 6, especially as a result of the contact of the screw head 9 with the conical widened portion 18, so that the hook element 4 rotates together with the screw 2 on account of the friction effective between the screw head 9 and the conical widened portion 18.
LIST OF REFERENCE SYMBOLS
[0037] 1 wall hook [0038] 2 screw [0039] 3 fixing element [0040] 4 hook element [0041] 5 stop element [0042] 6 anchoring substrate [0043] 7 shank [0044] 8 screw tip [0045] 9 screw head [0046] 10 thread [0047] 11 shank receiver [0048] 12 hook part [0049] 13 opening [0050] 14 rib [0051] 15 groove [0052] 16 tongue [0053] 17 counter-tongue [0054] 18 conical widened portion [0055] 19 spacer element [0056] 20 front part of the stop element 5 [0057] 21 hollow-cylindrical portion [0058] 22 hollow-cylindrical recess [0059] 23 predetermined breaking point [0060] E introduction direction [0061] L longitudinal axis
